Your PC is a pretty sad kind of icon - typically beige (groovy Macs notwithstanding) and invariably ugly, it hides its charms from all but the section of the population born with a genetic sympathy for complicated tech. It's certainly an unlikely candidate for the term revolutionary.

That's exactly what it has become, though, in the past two decades. The PC is now the greatest instrument of personal liberation in western cultures. That such an over-complicated, over-powered and over-priced box of tricks should continue to dominate the imagination of so many - geek and non-geek alike - even into the century of intelligent machines - is one of the more remarkable phenomena of the era. Before I attempt to explain the PC's improbable resilience, let's look at the case against it.

On the face of it, the PC is a dinosaur: a programmable, general-purpose computer in the era of the simplified, single-purpose tool. Any arm-chair futurologist will tell you that the PC must inevitably yield to a swarm of gadgets variously attached to your person, colonising your home (at about ankle height), discreetly re-stocking your fridge or representing your interests on the net while you sleep. Even your office PC doesn't really need to be a PC any more.

It should, by now, have become a "thin client" or a terminal of some kind hooked up to the net and downloading its intelligence and usefulness as it goes. Since you rarely use more than 5% of your PC's power, you're sitting in front of an absurd box of grossly over-engineered circuitry. Spinning fans and glowing heatsinks work incessantly to keep it from overheating while you play Solitaire.

Unnumbered gigaflops stand ready to play your Buffy MPegs without a jitter. Trillions of computing cycles are spent unproductively every day. Not only is the PC probably the most technically complex device you'll ever own, and probably the most complex ever mass-produced, it embodies so many criss-crossing economic, cultural and social factors that it's a miracle it works at all. In the future, goes the story, we'll look back on the era when we had one on every desk and wonder what on Earth we were thinking. In the meantime, though - at least a decade after the first firm predictions of its demise - it persists.

The resilience of the PC is really the resilience of a metaphor. Without its metaphorical clout the PC would have been relegated to the back room years ago - merging with the rest of the dumb infrastructure. A psychologist would call the PC "over-determined" - carrying a freight of cultural and psychological meaning far out of proportion to its apparent status. For its users, and particularly for the young, the PC is a liberated zone, a place of permission, autonomy, creativity and of almost unlimited possibilities. Very few man-made things can ever have carried so much meaning, condensed so much value and potential for action. It seems odd to ascribe such power to the cream-coloured lump on your desk but only a handful of contemporary cultural phenomena can match the PC's potential for connection with others and fulfilment.

The significance of the PC owes everything to the fact that most young people now grow up with regular access to a machine whose capabilities are limited only by the imagination. This generation does not feel the vertigo of tech-fear that makes the rest of us anxious, dulling our interaction with the networked world. It's no coincidence that the only people still predicting the PC's demise are the ones old enough to remember a time before it existed.

Forty-plus members of the technocratic elite can still be heard talking down the PC but only because they can still remember the IBM Selectric typewriter and can't get the hang of instant messaging. A generation growing up utterly at home with the transformative power of the PC is not going to give up on this richness without a fight. While quite rational adults worry about "total cost of ownership" and the economics of putting thousands of pounds worth of PC on your desk, its screensaver twirling pointlessly, the wired generation treasures the no-limits culture of the PC and won't be swapping theirs for a slimmed-down access device any time soon: if you don't have the tool you need, download it.

If it doesn't exist, code it yourself. If it works, upload it and make some money. The general purpose PC embodies such redundancy, over-capacity and waste that logic condemns it but, as we have learnt before, logic has little to do with the success or otherwise of technology products. The bond formed by millions of young people with their ugly duckling PCs will be an increasingly important factor in the post-crash tech economy. If you're still betting on the demise of the PC, you should be prepared for a long wait.